Grass family (Poaceae)
Description: This introduced perennial grass is 23½' tall and unbranched. The culm is light green, hairless, and terete (round in cross-section); the nodes of the culm are green and glabrous. The blades of the alternate leaves are up to 1/3" across and 9" long; they are dull green to greyish blue, hairless, flat, and linear. Their margins are scabrous, while the base of each leaf blade is usually more wide than the culm. The ligules have brittle papery membranes. The sheaths are dull green to greyish blue like the leaf blades. The culm terminates in a spike-like panicle of florets that is narrowly cylindrical; this inflorescence is up to 7" long and 1/3" across. The spikelets are densely packed together along the entire length of the inflorescence. Each spikelet is about 3.5 mm. long, consisting of 2 glumes that are appressed together and a single fertile lemma. Each glume is about 3.5 mm. long; it is ciliate along the keel and terminates in an awn that is shorter than the glume. The lemma is shorter than the glumes and enclosed by them; its upper margin is truncate and dentate. The lemma encloses a membranous palea with a single flower that consists of 3 stamens and a pair of feathery styles. The blooming period occurs during early to mid-summer and lasts about 2-3 weeks. During this time, the anthers of the flowers release prodigious amounts of pollen. As the grains ripen, the cylindrical panicles of spikelets become light brown. The root system consists of fibrous roots and short rhizomes. Tufts of plants are often formed, sometimes forming sizable colonies.
Cultivation: The preference is full or partial sun, mesic conditions, and a loam or clay-loam soil. This grass is somewhat aggressive in disturbed areas; it does not tolerate regular lawn-mowing.
Range & Habitat: Timothy is a common grass that occurs in every county of Illinois (see Distribution Map). It was introduced from Europe as a source of hay for horses and farm animals. Habitats include fields, disturbed meadows, fence rows, vacant lots, powerline clearances, roadsides, and waste areas. Timothy is still cultivated as an agricultural crop; it is found in disturbed areas more often than natural habitats.
Faunal Associations: Various insects feed on Timothy, including Aptinothrips rufus (Red Grass Thrip), which has been found in its seedheads. The caterpillars of the skippers Polites mystic (Long Dash) and Thymelicus lineola (European Skipper) feed on this grass, as do the caterpillars of the moths Leucania pseudargyria (False Wainscot), Oligia fractilinea (Lined Stalk Borer), and Cosmiotes illectella (Elachistid Leaf Miner). The seeds are eaten to some extent by the Bobwhite and a variety of granivorous songbirds (see Bird Table for a listing of these species). Mammalian herbivores graze on the foliage of Timothy, including the Cottontail Rabbit, White-Tailed Deer, horses, and cattle. Among small rodents, the Deer Mouse has been observed eating the seeds, while the Prairie Vole eats the leaves (see Whitaker, 1966; Cook et al., 1982).
Photographic Location: A powerline clearance in Busey Woods of Urbana, Illinois.
Comments: This charming grass has escaped from agricultural fields and can be found everywhere. The most distinctive feature of this grass is its narrowly cylindrical seedheads; the mature foliage is somewhat coarse. Unfortunately, Timothy is a major cause of allergies in some areas because it releases large amounts of pollen during the first half of summer. For this reason, some people may be less than charmed to find its presence in their neighborhood. While there are other grasses in Illinois that have cylindrical seedheads (e.g., Setaria spp. and Alopecurus spp.), their spikelets are usually more bristly and shiny from the presence of long hairs. The short hairs that are observable on the inflorescence of Timothy are actually paired awns of the spikelets. These awns are flexible rather than stiff while the spikelets are still green. This grass was named after a farmer who advocated its use during the early 18th century, hence the common name 'Timothy.'